Rheostat



A. F. VICTOR.

RHEOSTAT. APPLICATION Fl-LED JULY 17, I919.

Patented Jan 11, 1921.

2 SHEETS-SHEET 1.

A. F. VICTOR. RHEOSTAT.

APPLICATION FILED JULY 17, 1919.

7 1,364,967. Patented Jan. 11

. @LMEQ/MM h2g7 UNITED STATES PATENT OFFICE.

ALEXANDER FERDINAND vIc'roR, of jmvnnron'r, IOWA.

RHEQSTAT.

To allwhom it may com-em:

Be it known that I, ALEXANDER FnRnI NAND Vroron, a subject of the King of Sweden, (having declared my intention of becoming a citizen of the United States,)

residing at Davenport, in the county of Scott and State of Iowa, have invented new and useful Improvements in Rheostats, of which the following is a full, clear, and exact description. 1

My invention relates to improvements in rheostats, and its object is to greatly simplify and reducethe cost of the same-and, when it is manipulated,-to make the increase or decrease 0f.resistance, tothe electric current constant and so gradual that the transition from one resistance. to the other is hardly noticeable. This Iaccomplish by .the means hereinafter fully described, and asillustrated in the drawings, in which- Specif cation of Letters Patent.

Figure 1 is a plan view of my improved rheostat;

Fig. 2 is a central longitudinal sectional view of the same;

Fig. 3 is an end View thereof.

Fig. 4 is a transverse section taken on dotted line 4+4, Fig. 2.

Fig. 5 shows a side elevation of a modified construction of my invention.

Fig. 6 is a plan'view of yet another modification.

Referring to the drawings, A represents a fiat piece of suitable insulating material; B represents a resistance coil, one end of which is connected to a terminal a at one end of said plate and from thence has the convolutions thereof wound around the plate until the opposite end of said plate is reached,

whereupon its opposite end is connected to} the terminal b.

A longitudinal shaft C, which is, prefer ably, made of steel, extends across the convolutions of the resistance coil, and has one end projected beyond the vend edge of the plate and provided with a suitable handgrasp made of insulating material. This shaft is journaled in and kept pressing to- 1 ward said convolutions by laterally. disposed hooks 0, 0, made of spring wire. The shanks of these hooks are fastened by screws 01, d,

I to said: plate, between its end edges and the end convolutions ofthe coils, and the points plates. I

of the hooksextend through holes in said I nals a and b, in the circuit.

Patented Jan. 11, 1921.

Application filed July 17, 1919; Serial No. 311,483.

Between the hooks and the endconvolutions of the coil, shaft C has transverse holes made therein, andfthe ends of acopper wire E are bent inward and inserted and secured in these holes. I prefer to secure said ends by -collars e, e, mounted and secured on said shaft in suchposition that they impinge against and bite into the bent ends of the wire -E, but any other method of anchoring said ends will answer just as well. "From its ends, wire E is curved or made to describe spiralcourse's in the same direction until its'center of length is reached, and at this point it is'secured to shaft 0 by a staple F, one or both ends of which latter are embedded in and securely fastened to said shaft.

The curvature of wire E describes two reverse oorresponding spirals between its ends and ts center of length, constituting, as it, were, two'continulng contacts.

is revolved corresponding portions of each As shaft 0 of these spiral contacts come in contact with the convolutions of the .coil and cut out the electric current between their points of contact, and leave only the end portions 'of the coils between the convolutions enshaft C) is disposed vertically and has its journals 0 made of insulating material and jouriialed in the ends of L=shaped brackets g, g,-that are attached to and project from -a wall or other suitable support.

Between its journals this] shaft has a I copperwire E'secured thereto at its center by a staple F and which describe spiral courses around the shaft in the same manner as the wire E of the preferred form of my invention;

The ends of a vertical resistance coil are suitably scoured to brackets g, 9, so that .its axis is parallel to the axis of the shaft C and in such close propinquity thereto that when the shaft is turned on its axis the wire E will engage the outer circumference of the convolutions of the resistance coil and provide the duced by the wire E and the resistance coil shown in the first four figures of the drawin s.

n Fig. 6, I show yet another modified construction of -my invention in which the resistance coilB is wound around a tubular support 12 that is made of insulating mat teri'al.

-'with a longitudinal-groove 15 and a longi- This tubular support .is-provided tudinal shaft 10 1s looselyfseatedin this grooveand has its ends; extend beyond the provided with handles 16, 16,

r Shaft 10 has a wire E? secured thereto in of the resistance coil all the time.

embodiment of the principle the same manner as the wire E, and said shaft has its ends engaged by the free ends of, U-shapedsprings 13 that urge the shaft engaging the inner circumference of the convolutions By turning the shaft 10 the resistance. of the resistance coil is increased or decreased in the same manner as hereinbefore described.

All of these modifications and changes in construction affect only the mechanical of my invention, and I desire it to be understood that I claim them all as coming within its scope.

What I claim asnew is:

1. A rheostat comprising a resistance coil, and two integral longitudinally disposed rotatable spiral metal contacts engaging the convolutions of said coil; the curvature of one of said spirals being the reverse of the other.

2. A rheostat comprising a resistance coil, and two integral longitudinally disposed rotatable spiral metal contacts that yieldingly engage the convolutions of said coil; the curvature of one of said spirals being the reverse of the other.

3xA rheostat comprising a resistance coil,

an insulated support therefor, and two in-i tegral longitudinally disposed rotatable spiral metal contacts engaging the convolutions of said coil; the curvature of one of said spirals being the reverse of the other.

4. A rheostat comprising a resistance coil, aneinsulated support therefor, and two integral longitudinally disposed rotatable spiral metal contacts journaled in bearings attached to said support engaging the convolutions of said coil; curvature of one same. effect as is pro- -over said coil parallel to the of said spirals being the reverse of the other. 1

5. A rheostat comprising resistance coil, an insulated support therefor, and two integral longitudinally disposed rota-table spiral metal contacts journaled in bearings attached to said'support and yieldingly engaging the convolutions of said coil; the curvature of one of said spirals being the reverse of the other.

6. A rheostat comprising a resistance coil, a metal shaft extending longitudinally over the same, and two spiral metal contacts mounted on saidshaft that extends from each end of the same toward the center of length of the shaft in oppositely curved spiral courses and ,engaging the convolutions of said coil.

T. A rheostat comprising a resistance coil, a rotatable'metal shaft extending longituditudinally over said coil parallel to the axis of the same, and a wire contact having its ends secured to said shaft and extending from thence toward the center of length of the shaft in oppositely curved spiral courses, and engaging the convolutions of said coil.

8. A rheostat comprising a resistance coil, a plate of insulating material to which the terminals of said coil are secured, a rotata ble :metal shaft extending longitudinally axis of the same, a wire contact having its ends secured to said shaft and extending from thence toward the center of length of the shaft in oppositely curved spiral courses, and means fol: keeping said contact in engagement with the convolutions of said coil.

9. A rheostat comprising a resistance coil, a plate of insulating material to which the terminals of said coil are secured, a rotata ble metal shaft extending longitudinally over said coil parallel to .the axis of the same, a wire contact having its ends secured to said shaft and extending from thence toward the center of length of the shaft in oppositely curved spiral courses, and spring wire hooks in which the ends of said shaft are journaled and which keep said contact wire bearing against the convolutions of,

said coil.

In witness whereof I have hereunto set my hand and seal this 8th day of May, 1919.

ALEXANDER FERDINAND VICTOR. IVitnesses M. WEIDLEIN, E, BALLWEG. 

